In recent years, since there is a problem that a temperature rise of a permanent magnet in a hybrid vehicle or an EV vehicle using a rotary electric machine as a driving source, resulting in greatly affecting performance of the rotary electric machine, a technique for efficiently cooling the permanent magnet has been proposed.
In a driving system disclosed in patent literature 1, a refrigerant scraped upward by a gear, the refrigerant is supplied from the catch tank to a permanent magnet and a coil through a refrigerant passage formed inside an end face plate. Further, when the refrigerant is supplied to the refrigerant passage formed inside the end face plate, the refrigerant is supplied to a supply port of the end face plate from a cutout portion which is formed in a flange portion of a rotor shaft supporting the end face plate.